Cumacea: 17. Pseudocumatidae, 1. Petalosarsia 141 



Zool. .)ahrb., Syst. r. 18vi p. 694 | 1912 P., Caiman in: P. U. S. Mus., ?\4l p. 605 1 1912 

 Pseiidocamatidae, T. Stebbing in: Ann. S. Air. Mus., v. 18 v p. 133. 



Lobes of pseudorostrum contiguous from the eyelobe to the apex 

 (except in Schizorhynchus p. 143). Protuberances on the pedigerous segments 

 when present not spiniform. Pleon slender, smootli; telson small, lamellar, 

 not apically acute or subacute. Eyelolte varying iji shape, eye composed of 

 .3 or 2 corneal lenses or quite indistinct. Antenna 1 with accessory ttagellum 

 rudimentary. Antenna 2 in female very small, in male well developed. 

 Spines in spine-row of mandible not numerous, molar stout. Epipod of maxilli- 

 ped 1 scantily furnished with branchial leaflets, at least in the female. Maxilli- 

 ped :> with long '■1^'^ joint not apically i)roduced but furnished at the lateral 

 angle with a very long seta. First four pairs of peraeopods in the male 

 provided with exopods well developed, but only first two paii-s in the female, 

 the third and fourth pairs in that sex having the exopods represented by 

 more or less distinctly 2-jointed rudiments attached to the 2°'^ joint. The 

 first two segments of the pleon in the male have small pleopods, the first 

 distinctly 2-jointed, setiferous, the second almost rudimentary, with the 2'"^ 

 joint fused or diminutive. Uropods with 1 -jointed endopod. 



6 genera accepted, 1 doubtful. 



Synopsis of the accepted genera: 



, Peraeopod 1 with third and fourth joints firmly united 



I and the fifth abnormally dilated 1. Gen. Petalosarsia 



I Peraeopod 1 with third, fourth, and fifth joints normal 

 I in size and arrangement — 2. 



( Pseudorostral lobes not distally contiguous 2. Gen. Schizorhynehus 



^ \ Pseudorostral lobes distally contiguous — 3. 



. Fifth pleon segment not longer than broad; peduncle 



I of uropods very short 3. Gen. Caspiocuma 



\ Fifth pleon segment longer than broad; peduncle of 



' uropods not very short — 4. 



( Pedigerous segments, some or all, with dorsal pro- 



4 tuberances 4. Geu. Pterocuma 



I Pedigerous segments without dorsal protuberances — 5. 



) Body very slender 5. Geu. Stenoeuma 



^ i Body not specially slender 6. Gen. Pseudocuma 



1. Gen. Petalosarsia Stebbing 



1865 Petalopus (Sp. un.: P. declivis) (non Motschulski 1845), G. 0. Sars in: Forh. 

 Selsk. Christian., 1864 p. 196 | 1883 Petalomera (non Stimpson 1858), G. (J. Sars in: 

 Forh. Selsk. Christian., 1882 nr. 18 p. 13, 58 | 1893 Petalosarsia, T. Stebbing in: Int. 

 sci. Ser., r. 74 p. 308 | 1900 P., G. 0. Sars, Crust. Norway, v. 3 p. 77. 



In general character agreeing with Pseudocuma (p. 148), ])ut the eye 

 feebly developed, first antenna with second joint broadly lamellar and third 

 very small, second antenna of female distinctly two-jointed, and first peraeo- 

 pods abnormal in structure, the third and fourth joints being firmly united 

 to form a small cup for the very large foliaceous fifth joint, over the broad 

 distal end of which the slender sixth and seventh joints can be folded to 

 produce a subchelate arrangement; the small second pleopod simple. 



1 species. 



